CLAUDE_CODE_PROJECTS_SESSION
A Claude Code environment variable, read out of the shipped bundle. It has been in the build since v2.1.282, including the newest one read.
In some hosted sessions, WebFetch now returns an "Already fetched" note instead of fetching the same page with the same prompt again
Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.282.
In the changelogs
2Releases whose published page names CLAUDE_CODE_PROJECTS_SESSION.
-
v2.1.282
WebFetch can skip a repeated fetch and point back to the earlier result
In some hosted sessions, WebFetch now returns an "Already fetched" note instead of fetching the same page with the same prompt again
found in this entry's text
-
v2.1.282
WebFetch can skip a repeat fetch and point back to the earlier result
With
CLAUDE_CODE_PROJECTS_SESSIONset, WebFetch can skip fetching the same page with the same request again and refer Claude to the earlier resultfound in this entry's text
First cited
1The earliest release whose published evidence quoted CLAUDE_CODE_PROJECTS_SESSION was v2.1.282, 24 Sep 2026. That is the oldest release this project wrote about it, so it is a floor on the name's age and not the release that introduced it. It is not a presence reading: which builds carried the name is the table below.
Presence across releases
1Build by build
2One row per release since the first build this name was read out of. Absent means the build was read and the name was not in it, never mined means no bundle for that release was ever archived, and a declared type or a default is only ever what that release's own bundle stated.
Read out of the published npm bundle release by release, and out of Anthropic's own documentation as this site captured it. Nothing on this page is a description anybody here wrote about what the environment variable does. All environment variables.